As you are researching indexes for any surname, take time to consider any alternative spellings there might be.
A simple name like SMITH may be spelled as SMITHE, SMYTH, SMYTHE, SCHMITT, or SCHMIDT. That does not include any intentional misspellings and transcriptions errors.
Prepare, in advance, a list of possible spellings for all the surnames you are researching and take it with you as a prompter when doing research in libraries, archives and other sites. In addition, reverse the given name and surname. And don't forget to try using just initials.
When searching through a computerized index that includes a soundex be sure to utilize this feature. You'll have to weed through some of the undesirables, but I have personally found, it is almost always worth the effort! - cbh